[Column Spot] Five Centimeters Per Second

When they were twelve years old, a meeting under the cherry blossom tree convinced them that they would be together for life. At that time, he was running very fast in front at a speed of five kilometers per second, and he was chasing desperately behind him at a speed of five centimeters per second. Later, he slowed down his too-fast pace and stayed where he was and waited patiently, only to find that the person chasing behind him had started rushing far ahead at some point. He changed his entire life, but still failed to change the distance between them. Conception: